Coastal Systems

By Simon K. Haslett

Coastal Systems offers a concise introduction to the processes, landforms, ecosystems and management of this important global environment. Each chapter is illustrated and furnished with topical case studies from around the world. Introductory chapters establish the importance of coasts, and explain how they are studied within a systems framework; subsequent chapters explore the role of waves, tides, rivers and sea-level change in coastal evolution.

Students will benefit from summary points, themed boxes, engaging discussion questions and graded annotated guides to further reading at the end of each chapter. Additionally, a comprehensive glossary of technical terms, a new list of associated videos made by the author, and an extensive bibliography are provided. The comprehensive balance of illustrations and academic thought provides a well balanced view between the role of coastal catastrophes and gradual processes, also examining the impact humans and society have and continue to have on the coastal environment.

• Language: English
• Publisher: University of Wales Press
• Release date: Jul 20, 2016
• ISBN: 9781783169023

Book preview

COASTAL SYSTEMS

COASTAL SYSTEMS

THIRD EDITION

Simon K. Haslett

© Simon K. Haslett, 2016

First edition published by Routledge imprint of the Taylor & Francis Group in 2000, as part of the Routledge Introductions to Environment Series; second edition published in 2009.

All rights reserved. No part of this book may be reproduced in any material form (including photocopying or storing it in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright owner. Applications for the copyright owner’s written permission to reproduce any part of this publication should be addressed to the University of Wales Press, 10 Columbus Walk, Brigantine Place, Cardiff CF10 4UP.

www.uwp.co.uk

British Library CIP Data

A catalogue record for this book is available from the British Library

ISBN 978-1-78316-900-9

eISBN 978-1-78316-902-3

The right of Simon K. Haslett to be identified as author of this work has been asserted in accordance with sections 77 and 79 of the Copyright, Designs and Patents Act 1988.

Cover image: OxanaMahnac/Shutterstock

For Sam, Maya, Elinor and Rhiannon

CONTENTS

List of plates

List of figures

List of tables

List of boxes

Author’s preface to the first edition

Author’s preface to the second edition

Author’s preface to the third edition

Acknowledgements

Introduction

1Coastal systems: definitions, energy and classification

2Wave-dominated coastal systems

3Tidally-dominated coastal systems

4River-dominated coastal systems

5Sea level and the changing land-sea interface

6Coastal management issues

Conclusion

Glossary

Further reading

Videos by the author

Bibliography

LIST OF PLATES

1.1Small-scale rock structure influences the character of a coastline. Along the granite coast of western Brittany (France), two contrasting coasts exist.

1.2The rugged coast of Oregon (USA) is a good example of a leading edge coast.

1.3The trailing edge coast of eastern Australia.

2.1The influence of fetch on waves: (a) long fetch waves on the eastern Atlantic coast and (b) short fetch waves on the northeastern coast of Australia.

2.2The Japan tsunami, 11 March 2011, inundated coastal lowlands to around 5 km inland and, as here at Sukuiso in the Iwate prefecture, damaged and destroyed buildings, and caused significant loss of life.

2.3Types of shore platforms. (a) Type A or sloping shore platform and cliffs. (b) Type B or quasi-horizontal shore platform.

2.4Exposed beachrock and fallen trees, indicators of coral cay instability at Green Island, Great Barrier Reef, Australia.

2.5A groyne built to trap sand by interrupting longshore drift at Chapel St Leonards along Lincolnshire’s North Sea coast (UK).

2.6Beach cusps formed in a gravel storm beach east of Nash Point, Glamorgan Heritage Coast (Wales, UK).

2.7(a) Glacial till along the southern shores of Galway Bay (Ireland). (b) Gravel beaches along the Queensland coast north of Cairns (Australia). (c) Gravel barrier at Porlock (Somerset, UK).

2.8(a) A gravel barrier overwash fan at Ru Vein in the Baie d’Audierne (Brittany, France), and (b) a breach in the gravel barrier at Porlock (Somerset, UK).

2.9Beach birds of southern California.

2.10Embryo dunes forming in discrete mounds at Barneville (Normandy, France).

2.11Dune scarp formed during winter storms and persisting into the summer at Genets in the Baie de Mont St Michel (Normandy, France).

3.1A salt marsh cliff in the Baie de Mont St Michel (Normandy, France) showing distinct sediment couplets.

3.2A downstream view of a road embankment built across L’Aber Estuary (Brittany, France).

3.3Extensive cliffing of a salt marsh at Northwick Oaze in the Severn Estuary (UK).

3.4A nest of channels in a salt marsh tidal creek at Barneville (Normandy, France).

3.5Mangroves of the eastern Australian coastline.

4.1A mangrove-lined tidally influenced channel, Barron River Delta near Cairns, Queensland (Australia).

4.2The linear shore of the wave-dominated Shoalhaven Delta, New South Wales (Australia).

4.3The extensive delta plain of the Shoalhaven Delta, New South Wales (Australia).

4.4Cows grazing on levées of the Shoalhaven River, part of the Shoalhaven Delta, New South Wales (Australia).

4.5Before and after views showing the impact of Hurricane Katrina at Biloxi along the Gulf of Mexico coast.

5.1A fossil Pleistocene ‘raised beach’ at Plage de Mezpeurleuch, Brittany (France): (a) a stratified sequence; (b) a poorly sorted unit.

5.2Sediment coring in an isolation basin at Rumach, west coast of Scotland (UK).

5.3The coast of the Somerset Levels.

5.4Barrier rollover at Porlock (Somerset, UK).

6.1Quarrying of dune sand and gravel in St Ives Bay, Cornwall (UK) in 1996.

6.2Plage de Tronoan in the Baie d’Audierne (Brittany, France) in 1994.

6.3Infrastructure use of the coast is well illustrated by the view of the port of Penzance in Cornwall (UK).

6.4Strandline deposits of litter on Plage de Mezpeurleuch (Brittany, France).

6.5Caravans and motor-homes parked on a salt marsh at Mont St Michel (Normandy, France).

6.6Pointe du Raz in Brittany is the westernmost tip of mainland France and suffers intense tourist pressure.

6.7Vast accumulation of algae on Fautec Beach (Brittany, France).

6.8Information for tourists on the management zoning of Green Island in the Cairns section of the Great Barrier Reef Marine Park.

LIST OF FIGURES

1.1Endogenetic and exogenetic energy and processes and their contribution to the development of coastal landscapes.

1.2Types of systems.

1.3Types of equilibrium.

1.4Examples of feedback relationships in coastal systems. (a) Example of positive feedback. (b) Example of negative feedback.

1.5The distribution of the earth’s crustal plates and their various boundary types.

1.6Subdivision of the coastal zone using both morphological and wave process terminology.

2.1The distribution of global wave environments.

2.2(a) Wave description. (b) The circular orbit of an oscillatory wave.

2.3Wave progression through deep-to shallow-water processes.

2.4Wave shoaling.

2.5Wave refraction on an irregular coastline.

2.6Types of breaking waves as a function of wave-height, water depth and beach slope gradient.

2.7The creation of wind waves.

2.8A woodcut depicting the coastal flood of 30 January 1607 in the Bristol Channel and Severn Estuary, UK.

2.9Influences of geological structure (a and b) and lithology (c and d) on coastal cliff development.

2.10Mechanisms of cliff failure: (a) rotational slumping; (b) toppling failure.

2.11The geomorphology of a rocky coastline.

2.12(a) Negative feedback system between wave-energy, cliff retreat and platform expansion. (b) Profiles of shore platform morphology types.

2.13The geomorphology of a coral patch reef.

2.14Morphodynamic responses of barrier islands to changing environmental conditions.

2.15The general geomorphology and sedimentology of a beach.

2.16Beach profiles surveyed over a ten-year period (1997–2007) at Ru Vein, a gravel beach/barrier, in the Baie d’Audierne (Brittany, France).

2.17(a) Longshore drift. (b) Formation of spits and baymouth bars as a consequence of longshore drift. (c) Formation of a tombolo.

2.18The development of rip currents along a swash-aligned beach.

2.19Beach cusp stability in relation to swash circulation.

2.20(a) Comparison of wind velocity over bare sand and grass. (b) Fluid and impact threshold velocities for different particle sizes.

2.21The formation (a) and migration (b and c) of sand dunes, also indicating the development of internal cross-bedding.

2.22(a) Geomorphology of a coastal dune system. (b) The distribution and influence of some environmental parameters affecting coastal dunes.

3.1The formation of the tidal bulge with regard to the relative position of the earth, moon and sun.

3.2Examples of semi-diurnal, mixed and diurnal tidal cycles.

3.3The distribution of semi-diurnal, mixed and diurnal tidal cycles around the global coastline.

3.4The amphidromic systems in the seas around the British Isles.

3.5Areas of the Ganges–Brahmaputra Delta prone to flooding to depths greater than 90 cm.

3.6(a) The distribution of tidal ranges around the global coastline. (b) The variation of tidal range during monthly tidal cycles. (c) Coastal geomorphological features associated with the various tidal range categories.

3.7The geomorphological significance of tidal range.

3.8Tidal current activity and sediment deposition.

3.9A series of bar-built estuaries on the coast of Cardigan Bay (Wales, UK).

3.10Estuary types according to Pritchard’s (1955) salt-balance principle classification.

3.11(a) Sediment pathways in an estuarine system. (b) The mechanics of settling lag.

3.12Various salt marsh settings in tidal environments.

3.13Three categories of salt marsh shorelines.

3.14A model predicting sediment deposition and distribution upon quasi-horizontal salt marsh surfaces.

3.15The relationship between horizontal erosion and accretion in determining salt marsh shore regime.

3.16Alternating negative and positive salt marsh shore regimes.

3.17The influence of salt marsh shoreline position on temporal grain size distribution.

4.1The relationship between delta dynamics and river, wave and tidal influences.

4.2Classification of modern deltas based on dominant processes (waves, tides and rivers).

4.3Extension of the delta classification scheme to incorporate sediment particle size.

4.4Three types of delta hydrodynamics based on the density differences between river and sea/lake water.

4.5General structure of a delta, indicating the location of topset, foreset and bottomset beds.

4.6Schematic geomorphology of a river delta.

4.7Schematic geomorphology of fan deltas.

4.8Shoalhaven Delta and its environments.

4.9The relationships and feedbacks between some examples of human activity and the dynamics of a delta system.

5.1The relationship between eustatic and isostatic changes and their influence on relative sea level and coastal emergence/submergence.

5.2Stages in glacio-isostasy, from ice-loading and crustal depression to deglaciation and isostatic rebound.

5.3Isostatic map of Great Britain.

5.4The distribution of submerged forests in Great Britain.

5.5Sea-level rise and the development of the coastline of the British Isles.

5.6Holocene peat and clay overlying solid bedrock.

5.7The relationship of foraminifera distribution to tidal levels and salt marsh environments in the Severn Estuary (UK).

5.8The relationship between the value of coastal land and the cost of protecting that coastline.

6.1Coastal zoning approach to coastal management in the Cairns section of the Great Barrier Reef Marine Park (Australia).

6.2The zoning plan for Green Island in the Cairns section of the Great Barrier Reef Marine Park (Australia).

LIST OF TABLES

2.1The zonal distribution of characteristic organisms in relation to tide levels on a rocky shore.

4.1Traditional categorisation of deltas according to their overall plan morphology.

4.2Examples of deltas and their river, sediment, delta plain and coastal environment characteristics.

4.3Comparison of terms describing the sediment structure, morphology and processes that operate in the three major deltaic areas.

5.1The distribution of biological structures in relation to sea level on rocky coasts.

5.2Estimated rates of sea-level rise obtained from tide gauges and satellite altimetry measurements.

5.3Projected global sea-level rise.

6.1A summary of engineered coastal protection measures.

6.2Heritage Coasts of England.

LIST OF BOXES

AUTHOR’S PREFACE TO THE FIRST EDITION

In 1998 I undertook fieldwork along the coast of northern Queensland in Australia, and at each beach I visited there were signs alerting visitors to various hazards. These included dangerous currents, stinging jellyfish, saltwater crocodiles, sunburn, and even falling coconuts! Being forewarned, I was able to enjoy investigating the various locations. However, there is a very serious message embedded in this: that coasts command respect. In recent years there have been a number of major coastal disasters resulting in thousands of casualties, including the Papua New Guinea tsunami in 1998, the Orissa storm surge in the Bay of Bengal in 1999, and the devastating flooding of the coastal lowlands of Mozambique in 2000 (some of these are discussed further in this book).

Around three billion people live in the coastal zone, that is half of the world’s entire human population. It is no wonder then that coasts are under pressure. Indeed, it is a major challenge for the twenty-first century for humans to live and work at, and exploit, coasts in a way that does not damage the environment or deplete resources, and that we will pass on to our children that which we inherited from previous generations. If we are to achieve this goal of sustainable development, then we should be striving to understand better how physical and ecological coastal systems operate, and then work alongside these, and not battle against them.

It has been my intention in writing this book to introduce to the reader our current understanding of coastal systems, including the physical, ecological and human interactions, so as to raise an awareness of the diversity and sensitivity of these precious environments. To conform with the ‘Introductions to Environment’ series, this book has been written for first- and second-year undergraduate audiences studying coastal systems as a one-semester module. Out of necessity, therefore, the text proceeds from first principles, but I hope that there is sufficient detail herein to satisfy more advanced readers. To this end, I have carefully selected references for further reading.

I have been supported for many years in my oceanographic research by a large number of people and to all of them I am very grateful. In particular, I am indebted to my wife Sam and my children Maya, Elinor and Rhiannon, for their patience, encouragement and companionship in my oceanic endeavours, and to my parents for fostering my environmental interests from a very early age. My professional development has benefited greatly from my mentors Brian Funnell, John Murray, Rick Curr, Ted Bryant, Annika Sanfilippo and Allan Williams. Also, all my colleagues at Bath Spa University College have offered very sympathetic support to me whilst I have been writing this book, especially Paul Davies and Fiona Strawbridge who have been brave enough to embark on coastal research collaborations with me. I am also very grateful to Kevin Kennington, Andy Cundy and Chris Spencer for taking the time to digest the first draft of the text and to offer very constructive comments. Finally, thanks to Ann Michael and Casey Mein at Routledge for making the writing of this book as painless as possible.

Simon K. Haslett

Newton Park, Bath

April 2000

AUTHOR’S PREFACE TO THE SECOND EDITION

In the opening paragraph of my preface to the first edition of Coastal Systems I stressed that coasts command respect and went on to mention some of the unfortunate coastal disasters that had occurred just before 2000, such as the 1998 Papua New Guinea tsunami and the 1999 Indian storm surge, both of which claimed lives running into several thousands. Events since 2000 show that such disasters are not isolated occurrences but contribute to an ongoing and terrible catalogue of coastal catastrophes. For then, in 2004 a tsunami affected the entire coastline of the Indian Ocean killing over a quarter of a million people, and in the following year the landfall of Hurricane Katrina in the United States caused death and destruction to areas around the Gulf of Mexico, showing that coastal disasters are not restricted to the developing world. Moreover, just as I was finishing the draft of this second edition yet another storm surge struck Bangladesh, again claiming thousands of lives – at the last minute I rewrote a section of the book to include this timely reminder of the respect that society should always pay to the coast, no matter where you are in the world.

This message underpins the societal value of studying coastal systems, allowing us to better understand how this complex environment developed through time, how it operates on different time and spatial scales, and what it may do in the future. Part of the future development of coastlines depends on human activity and the impacts of society, either through direct influence, such as quarrying coastal sediments, or indirectly through agents such as anthropogenic climate change. Indeed, this second edition has been timed to incorporate the latest predictions of the Intergovernmental Panel on Climate Change published in September 2007, which reiterate that not only may sea level rise as a result of global warming but that increases in storms and their severity are likely to exacerbate coastal erosion and flooding in many areas of the globe. This is an issue in which every individual on earth has a vested interest and is able to affect the outcome, for better or worse, depending on whether they are able to change their lifestyles to reduce greenhouse gas emissions or not.

I feel it is important for a textbook like this to arrest the attention of readers and to draw them into this highly interesting and often exciting field of study. Armed with the basic principles provided by this book I hope the student will be inspired enough to read further, undertake a field project, contemplate further study, and even consider a related career. The majority of reviews for the first edition, for which I’m grateful, have encouraged me to think that the format, scope and content of the book appeal to a wide audience of undergraduate students following a number of different discipline pathways, and for that reason I have not made any extensive changes to the book. My main aim for this second edition is to make it more appealing to the next generation of coastal science students by updating the ever-growing literature base and including examples that have occurred relatively recently and so would be familiar to students just entering university. I have also added further guidance to reading, which is becoming more and more bewildering with the expansion of online literature databases.

Since 2000 my coastal research has diversified somewhat and has benefited greatly through collaboration with other coastal scientists. I particularly want to acknowledge the pleasure I have had, and knowledge I have gained, at both ends of the analytical spectrum, through close collaboration with Professor John R. L. Allen (University of Reading) and Dr Ted Bryant (University of Wollongong). Whereas with John, we have been working on highly detailed analyses of estuarine sediments and landforms, sometimes at the sub-millimetre scale, to painstakingly piece together coastal evolution in relation to sea-level change over millennia, Ted and I have undertaken relatively broad-brush field studies of the impact of tsunami and storms along extensive coastal landscapes at single points in time. Such divergence of approaches and spatiotemporal contexts is very insightful and has shown me that one may never stop learning about the coast, even if you’ve written a textbook on the subject! I would also like to acknowledge other coastal colleagues to whom I want to signal my continued appreciation: Dr Andy Cundy (University of Brighton), Professor Roland Gehrels (University of Plymouth), Professor Jon Nott (James Cook University), Dr Chris Spencer (University of the West of England), and Dr Colin Woodroffe (University of Wollongong). My thanks also go to Andrew Mould and his team at Routledge for encouraging me to propose this second edition and for working with me on it, and to my colleagues of Bath Spa University for easing the task of writing and to the generations of students I have taught for helping to shape the content of the book.

Finally, I would like to endlessly thank my wife Sam and daughters Maya, Elinor and Rhiannon, for allowing me to indulge my interests and to follow this career, which often demands of me more than I’m paid to do and so takes time away that I could be spending with them. Thank you.

Simon K. Haslett

Newton Park, Bath

January 2008

AUTHOR’S PREFACE TO THE THIRD EDITION

Since the publication of the first edition of Coastal Systems in 2000 the need for a better understanding of coastlines and the factors that affect them has become increasingly clear. The coast demands respect as a place to live, work and to take leisure, and the global human population increase continues to place an ever-growing burden on coastal resources and impacts on the coastal environment and its sustainability. For these reasons, education about the coast as a global environmental feature is a necessity and has been my inspiration to compile a third edition of the book to provide an updated introduction for a new generation of students.

Between the publication of the first and the second edition of Coastal Systems in 2008, devastating coastal hazards occurred, such as the Indian Ocean tsunami of 2004 and Hurricane Katrina in 2005. However, since 2008, a number of further disasters have befallen the coast, such as Cyclone Nargis and its storm surge in the Bay of Bengal late in 2008, the Japan tsunami of 2011, Hurricane Sandy and its flooding of coastal New York City in 2012, and the impact of storm surges spawned by Typhoon Haiyan in the Philippines in 2013. In summary, since 2000, there is a growing list of coastal catastrophes that have caused extensive damage and tragic loss of life. To add to these events, as the 21st century progresses, there is an ongoing background rise in sea level due to climate change that is beginning to have noticeable impacts on coastlines worldwide.

The third edition has been updated to incorporate reference to these events and to include headline data from the most recent report of the Intergovernmental Panel on Climate Change (IPCC). Indeed, it was the publication of this IPCC report in 2014 that urged me to begin work on this edition. I am grateful to Routledge, the publishers of the first two editions, for discussing my proposal for a third edition and for their support and assistance in transferring the rights of the book to the University of Wales Press whom I’m delighted to be publishing with. I appreciate the guidance and patience of Sarah Lewis and her colleagues at the Press for bringing this edition to print. However, the format of the book has been retained which, as originally envisaged by Routledge in their Introductions to Environment Series, allows revisions and updates to be made readily without the major rewriting of text. My intention for this edition has been to update the text only where required, mainly with new case studies, and adding and updating references to support understanding and offer examples. I have also compiled a new list of streamed videos that I have produced that support many of the topics covered by the book.

Since 2010, I have worked as a senior manager at the University of Wales in Cardiff and recently have also begun working across the University of Wales Trinity Saint David ahead of a planned merger between the two institutions. This has given rise to the opportunity to develop a Coastal and Marine Research Group across the universities and I am delighted now to be establishing collaborations with colleagues with a view to extending my coastal research activity. In the prefaces of both previous editions I give thanks to many a number of colleagues, to whom I am still grateful, but I also remain eternally indebted to my wife Sam and children Maya, Elinor and Rhiannon for their continued support and understanding in keeping my coastal research interests alive. Thank you.

Simon K. Haslett

The Registry, Cardiff

January 2016

ACKNOWLEDGEMENTS

All reasonable efforts have been made to locate copyright holders to reproduce illustrative material from third parties in this work. The author and publisher would like to thank the following for granting permission to reproduce images.

Allen, J. R. L., 1993. Muddy alluvial coasts of Britain: field criteria for shoreline position and movement in the recent past. Proceedings of the Geologists’ Association, 104.